On the small farm in Oakdale where Michael Mendes grew up, there was a little walnut orchard.

He didn't know it then, but his future was written in those tree leaves.

Today, the 47-year-old son of Azorean immigrants is the CEO of Diamond Foods, the snack-making offspring of the Diamond cooperative founded in 1912 by a group of California walnut growers.

While Mendes chalks up his career in the food industry to coincidence - upon graduation from UCLA it was a toss-up between that and becoming a currency trader in Hong Kong - his childhood experience in rural Stanislaus County has served him well.

"It was a background that was a nice reference point as I evolved in the food business," he said in a recent interview at Diamond Foods' headquarters on the 17th floor of the Transamerica Pyramid, one of the only high-rises where moving down a few floors, as Diamond has, means your outfit is growing.

"I learned an extremely hard work ethic and exacting attention to detail," he said.

Mendes' interest in international marketing led him to turn down the currency-trading opportunity and throw in with Dole Food Co.

In 1991, Mendes joined Diamond Foods as vice president of sales and marketing. He took his place in the top spot six years later.

Along the way, he met and married Wendy Berry, a research social psychophysiologist who is leaving a six-year post at Harvard University to assume an endowed chair at UCSF. As fate would have it, her speciality is coping with stress.

A lot has changed for the snack company since Mendes signed on: In July 2005, he led Diamond's initial public offering on the Nasdaq exchange, where it has enjoyed 13 straight quarters of growth. In 2008 came the acquisition of Pop Secret from General Mills Inc.; this year, Diamond picked up potato-chip maker Kettle Foods for $615 million.

With the addition of the latter, Mendes said, the company is expected to nearly double its sales to $1 billion this fiscal year.

Meanwhile, the Emerald brand of snacks introduced eight years ago has risen to No. 2 among its competitors.

Nut growers inspire

Mendes is quick to deflect personal credit for the success. Instead, he invokes the vision of the founding farmers and the collaborative culture he is proud of fostering among his 1,600-plus employees.

"I was always quite taken by these walnut farmers," he said. "It used to be it took a tree six or seven years to come to production. Then you have to farm for six or seven years to make enough money to cover the cost of the trees. You wouldn't even break even for 14 years. Then you hope the trees last for 45 or 50 years - now that's long-term planning.

"I've been respectful of looking back and learning and extracting the wisdom of the past and applying it to the future."

As for his current staff, he said, "The screening filter for our leadership team is a sense of humility and a deep desire to collaborate, people who get great pleasure from winning as a team. It's less common than I would have hoped of a trait in senior leaders, because a lot of what gets people to the top is winning as an individual."

Admit mistakes

Take the short-lived shelf life of the company's wasabi-flavored peanuts, for example.

"As much as I don't like to make mistakes, once I've made a mistake, I take great delight in disparaging myself to the management team, as they feel like, if the big guy can take a hit ..." Mendes said. "We laugh a lot around here, and we like to amuse each other."

Indeed, as the brand increases its presence in the United Kingdom, Europe, Asia and South America, trial and error is par for the course.

"There are significant changes in preference in terms of taste and textures," he said. "In a market like Japan, a very popular snack nut mix includes dry fish. In the U.K., one of our best selling chips is beef-flavored. The texture of our chip in the U.K. is distinctly different from the U.S. - it actually has a softer bite. The flavor profiles are evolved and are very distinct by market. It's amazing, the nuance."

He recalls a business trip to Finland early in his career.

"Our business partner was treating me to a special Finnish snack, which was honey and pickles," he said. "And I have to tell you, it's something. It'll surprise you."

But don't expect it to be offered under the Diamond Foods label anytime soon.

Michael Mendes

Work: CEO, Diamond Foods (Nasdaq: DMND)

Age: 47

Family: Wife, Wendy Berry Mendes; daughter, Blair, 7

Residence: Cow Hollow, San Francisco

Hobbies: Running, triathlons

Quote: "The No. 1 thing I look for in people is a strong capability for resilience. ... I characterize us as a company that does well when it comes to the hills. We like hills."